August 27, 2016

1 - The summer moisture has arrived and now we find the benign and interesting slime mold organisms in our gardens.

Q.

I have some sort of mold growing in my yard. It is not the usual toadstool / mushroom I see growing from dead roots in the ground. This is some kind of a white blob that encompasses the grass, sticks and even my garden hose. It cannot be cut out as it does not seem to have a root and will take the grass with it. It is very wet and seems to be full of water. When I walk across the grass, I can feel the lumps as they start growing. If one gets tall enough and I hit it with the lawn mower, it becomes a wet mess.

Any help you can give me with identifying this growth (blob) would be most helpful and especially on how to get rid of it. Shades of Steve McQueen.

- Bill M.

A.

While I cannot be sure without seeing this "blob", I think you are describing an interesting organism called slime mold. Some people say it looks like dog vomit or other such things. It may be white, pink, yellow, orange, and other colors.

When I was a student in university, these were considered to be related to fungi. However, now they are considered a totally different type of organism. Their life history reveals that they are indeed unique. They live much of their lives as independent cells feeding on decaying, dead organic matter (lawn thatch, organic mulch, manure, dead leaves, etc.). They also feed on bacteria and fungi. When environmental conditions are proper, they begin to gather together to form a single structure (the blob you are seeing) and then develop spores to reproduce. There are many types of unrelated slime molds that have variations in this life history. In one article I read, if they are separated as they have begun to form the blob, they will reconnect. Yes, they are very interesting and weird organisms.

In our New Mexico environment they become most obvious, and I get questions about them, during the monsoon season when there is moisture. In locations with irrigation, they may develop at other times during the warm season. Since they are decomposers, they are actually beneficial in that they release nutrients from dead material to return the nutrients to the soil for living plants to use. They rarely cause damage to living plants. Trying to prevent them is futile. The common recommendation is to "let nature run its course". They will eventually form their spores, and then the blob will dry up and blow away. You can try washing it away with a strong stream of water, but that may actually cause it to increase before it has dried up. Once it is dry it should wash away without problem.


Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

Links:

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